Ok. Not quite gravitational waves in the true sense.
Last paragraph...
*Note that gravity waves shouldn’t be confused with “gravitational waves,” waves in spacetime created as objects move through space.
(Perhaps they should not be called gravity waves).
Sure they're not pressure / shock waves?
It has been removed.
What does the xK denote towards the bottom of the graph?
It isn't more advanced than you think. A pipe dream at best.